The present invention broadly relates to a new and improved construction of an arrangement for locking a breechblock head in a predetermined position at the rear end of a weapon barrel.
In its more particular aspects, the present invention relates to a new and improved construction of an arrangement for locking a breechblock head in a predetermined position at the rear end of a weapon barrel of a firing weapon containing a reciprocatable breechblock head. This rear end of the weapon barrel possesses an internal circumferential groove which follows, in a forward direction of the weapon barrel, an inner annular flange with teeth forming an inner gear toothing. The breechblock head possesses teeth forming an outer gear toothing. In the predetermined locked position of the breechblock head, the teeth forming the outer gear toothing provided at the breechblock head are located in the internal circumferential groove or locking space and these teeth bear upon the teeth of the inner gear toothing provided at the inner annular flange of the weapon barrel.
A locking arrangement for linearly movable breechblocks in hand firearms as known, for example, from Swiss patent No. 51,131, granted Mar. 9, 1910, contains a breechblock member which is locked at a breechblock housing. During this operation, locking lugs which are provided at a rotatable cylinder of the breechblock are turned or rotated in recesses or locking recesses which are provided at the ends of guide grooves guiding the locking lugs.
Side walls of the locking recesses possess components which form a large angle of inclination with a longitudinal axis of the guide grooves. Further side wall components follow the aforementioned components and the guide grooves and form a smaller angle of inclination with the longitudinal axis of the guide grooves. Upon unlocking the breechblock head, empty cartridge cases are gradually loosened by means of the first mentioned side wall components and the breechblock member is pushed backwards by the further side wall components in order to effect a partial withdrawal of the fired cartridge shells from the weapon barrel.
It has been shown that the forward moving breechblock head rebounds at the weapon barrel and thus there exists the danger that the teeth forming the inner gear toothing of the weapon barrel as well as the teeth forming the outer gear toothing at the breechblock head will be damaged during the breechblock locking operation. The danger of such rebound is particularly pronounced in a Gatling gun in which the breechblock head respectively moves at the start and at the end of a continuous or series firing operation without a cartridge being inserted into the weapon barrel. The danger of the aforementioned rebound further exists in an externally powered weapon or gun containing a positively reciprocated breechblock which possesses a curve or cam follower roll which is guided by a control cam and by means of which the breechblock is reciprocated.
In order to avoid this rebound the breechblock should no longer possess any velocity when arriving at its foremost position, i.e. the control cam would have to possess zero slope exactly at this location. The impact energy could be reduced by changing the shape of the control cam.